Redhawk shallow twist grooves

[edrice]

I just received a Ruger Redhawk 4" .45 Colt and looking down the bore the twist grooves seem rather light, lacking depth. This is especially in comparison to my 625 Mountain Gun also in .45 Colt, which has relatively deep twist grooves. They stand out when lit. The Redhawk grooves do not.

The Redhawk was sold as NIB on GunsAmerica and in every other respect it appears to be a new firearm, tight with mint cosmetics. It appears to have had no prior use except that there was powder in the barrel and the front of the cylinder is a bit blackish, which could have been from test firing. It somes from a seller with a flawless record.

Does the Ruger Redhawk have shallower twist gooves than the Smith or is this a shot-out barrel?

Ed

 

[rcmodel]

S&W used to use very deep cut rifling in deference to lead bullet use which was the norm. Jacketed bullets had barely been invented yet 40 years ago.
Now, they use very shallow rifling too because everyone shoots jacketed bullets and the rifling doesn't need to be as deep.

You gun sounds perfectly normal in this day & age.

rc

 

[edrice]

The Smith 625 Mountain Gun is also of recent vintage, only a couple of years old. I didn't mention that I also compared the bore to my Security and Speed Sixes, noting that they were more akin to the S&W 625 than the Redhawk. I used to have a Vaquero in .45 Colt and don't remember it looking like this. But maybe they were expecting more lead bullets from the Vaquero. I don't know.

Also the fact that once upon a time I ordered a used Security-Six barrel from Numrich and when I received it, it was pretty much shot out. Quite smooth looking. I sent it back and found another one on ebay (back when ebay permitted that sort of thing) and that one was much better and had some higher lands to it.

The Redhawk barrel remembles that used Numrich barrel and that's what got me started. I called Ruger and they said that Redhawk left Ruger in April 09, so that hardly seems like time enough to smooth a barrel down.

You are probably right, that it's OK, but now I'm curious as to how it would do with lead bullets with lands that low. They would probably need to be hardcast if at all.
Ed

 

[rcmodel]

My only suggestin beside shooting it and seeing how it does is:

Buy a pack of lead egg sinkers and slug the bore and measure it.

It should slug .452".
If its way bigger then that, then contact Ruger as it has to be a manufacturing error on a new gun.

rc

 

[edrice]

It should slug .452".

Now this brings up an interesting question. While I had Ruger technical support on the phone, he gave me the dimensions of the groove diameter and width. That was all he had. The width was .156 and the diameter of the grooves was .450. He couldn't give me the height of the lands. I guess I could mike it, but haven't tried this yet.

Does this mean that Ruger is squeezing the .452 projectile down to .450, maybe making the shallower lands more effective? Would that make sense?

I admit I haven't ever fired it yet. I only picked it up Monday and haven't had a chance to get to the range yet. Also I wanted to leave it unfired in case there was reason that it should be returned.

Ed

 

[rcmodel]

Actual bore diameter of any barrel is always less then the groove diameter, or bullet diameter.

For instance, the actual reamed hole in a conventionally rifled 30-06 is .300".
After rifling, the measured bore diameter is .308". (.004" deep rifling grooves x 2)

All bullets are always squeezed down to the depth of the rifling lands and engraved with grooves. Yet the bullet fits the base of the grooves exactly..

A .45 Colt would have a .450" or less hole drilled & reamed, and then rifling cut.
When you slug the barrel to measure the bore, you are measuring the groove dia, not the land or hole size.
In the case of a .450" bore, the rifling would only be .001 deep on each side, making it .452"..

Were the hole reamed .448", you would have .002" deep rifling on each groove and a .452" slug measurement..
Older .45 Colts were often found with .454" bores & deeper rifling.

The only actual way to know what your barrel measures is to slug the bore with a lead slug, and measure the land & groove dia of the slug.

As long as your barrel has an equal number of lands & grooves, the slug is easily measured with a dial caliper.
If it has an unequal number, it becomes problematic to measure the slug without a dial indicator set-up.

rc